149 



Chelydra serpentina, (Linn.). 

 Snapper; Snapping Turtle. 



Testudo serpentina, Linnseus, 1758, 6^, ed. x, 199 ; Chelydra serpentina, 

 Schweigger, 1814, 88, 24; Agassiz, 1857, 4., i, 417, and ii, pi. iv, figs. 

 13-16, pi. vii, figs. 24-26 ; Boulenger, 1889, 84, 20, vviih figs. Ghelo- 

 nura serpentina, Holbrook, 1842, 54, i, 139, pi. 23. 



Carapace broad and rather depressed, highest in front aud notched 

 behind. A median and two lateral, tuberculated keels, disappearing la.te 

 in life. Marginal plates, exclusive of nuchal, 23. V<;rtebral scutes 

 wider than long, tuberculated behind. Costal scutes tuberculated near 

 the upper posterior angle. Plastron small, leaving the limbs exposed; 

 covered with five pairs of scutes ; the bridge very narrow. Two or three 

 inframarginals at the outer end of the bridge. 



Head large and flattened above, with rather conspicuous bony ridges ; 

 tapering, but not descending toward the snout. Eyes directed upward 

 and outward. Feet broad and webbed to tlie nails. Fingers five, all 

 with nails. Toes five, the outer one without a nail. The outer border of 

 all the limbs with a sharp fold of skin which greatly increases the surface 

 of the limb, as aid in swimming. Tail long and pointed, equaling the 

 length of the plastron. Tail furnished above with a median row of large 

 horny tubercles, supported by a bony core Each side of the tail with 

 smaller tubercles. Under side of tail with two rows of large scales. 



Skin of neck, under jaw, body, limbs aud tail covered with wrinkles 

 and large and small warts. Fore-arm and hands and feet with large, 

 overlapping, sharp-edged scales. Color of the carapace chestnut brown to 

 black. Plastron and soft skin whitish or yellow. Head and upper neck 

 brown. Attains a total length, it is said, of four and a half feet, the 

 shell two feet, usually much smaller. The weight may reach from 20 

 to 30 pounds. 



This species has a remarkably wide distribution. It occurs from Nova 

 Scotia to Ecuador, in South America. Westward it probably extends to 

 the Rocky Mountains. It is found, no doubt, in every stream and pond 

 in the State of Indiana. 



Habits. — This turtle spends the greater portion of its life in, or closely 

 about, streams and lakes and ponds. Although found living in clear rivers, 

 it appears to prefer muddy ponds. It is often seen far away from any 

 water, walking along with awkward and halting gait. Its mode of loco- 

 motion has been compared with that of the alligator. When seen on the 

 land it may be seeking some spot in which to deposit its eggs, or seeking 

 for food, or perhaps crossing from one stream to another. In the water 

 they do not seem to swim, but they may often be seen floating along just 



